The main objective of this research plan is to study several aspects of fluid and electrolyte transport in ocular membranes contributing to the maintenance of normal corneal and lens transparency. The movement of water and ions across the cornea and lens depends on two factors: a) the permeability of the membrane determined by the physical and histological structure, and b) the driving forces mainly produced by local or distant energy yielding chemical reactions. Although each of these two individual factors have been separately studied in cornea and lens, the way in which they are coupled to produce the resulting translocation of ions remains poorly understood. Using the formalism of the irreversible thermodynamics, emphasis will be put on the link of metabolism to ionic and water transport. Emphasis will be placed on the effect of pharmacological agents on ionic and fluid movement and on corneal and lens hydration as a means to understand the interrelation between metabolic forces and ionic and fluid pathways. Drugs to be used include transport inhibitors, such as diuretics and serotonin analogs and stimulants such as catecholamines, ascorbic acid, and amphotericin-B. ATPase enzymes will be isolated from corneal epithelium and their ionic activation studied. Frog, rabbit, and calf eyes will be used in these studies.